One method of treating a subterranean formation is fracturing. Fracturing is a process of initiating and subsequently propagating a crack or fracture in a rock layer. Fracturing enables the production of hydrocarbons from rock formations deep below the earth's surface (e.g., from 2,000 to 20,000 feet). At such depth, the formation may lack sufficient porosity and permeability (conductivity) to allow hydrocarbons to flow from the rock into a wellbore at economic rates. Manmade fractures start at a predetermined depth in a wellbore drilled into the reservoir rock formation and extend outward into a targeted area of the formation. Fracturing works by providing a conductive path connecting a larger area of the reservoir to the wellbore, thereby increasing the area from which hydrocarbons can be recovered from the targeted formation. Many fractures are created by hydraulic fracturing, or injecting fluid under pressure into the wellbore. A proppant introduced into the injected fluid may maintain the fracture width. Common proppants include grains of sand, ceramic or other particulates, to prevent the fractures from closing when the injection ceases. Some proppant materials are expensive and may be unsuitable for maintaining initial conductivity. The transport of the proppant materials can be costly, and ineffective. For example, proppant can have a tendency to settle in slick water jobs having short fracture lengths. Additionally, Slick water fracturing jobs demands the use of vast amounts of water and hydraulic horsepower. Gel jobs have also difficulties associated with proper clean up due to residue that contaminates the reservoir, impairing production, and the inability to stay functional (high viscosity) for long periods of time (5 to 24 hours) in formations that are tight and have long fracture closure times.
A method for providing permeability in fractures is described in U.S. Pat. No. 7,044,224. The method involves injecting a permeable cement composition, including a degradable material, into a subterranean formation. The degradation of the degradable material forms voids in a resulting proppant matrix. A problem of the method is that the degradation of the degradable material is difficult to manage. If the degradable material is not mixed uniformly into the cement composition, permeability may be limited. Furthermore, when degradation occurs too quickly, the cement composition fills the voids prior to forming a matrix resulting in decreased permeability. When degradation occurs too slowly, the voids lack connectivity to one another, also resulting in decreased permeability. In order for degradation to occur at the proper time, various conditions (such as pH, temperature, pressure, etc.) must be managed carefully, adding complexity and thus time and cost to the process. Another problem of the method is that the degradable material can be expensive and difficult to transport. Yet another problem of the method is that, even when large amounts of degradable material are used, permeability is only marginally enhanced. Furthermore, the addition of degradable material can have negative impact on flowability.